A multimarker multi-time point-based risk stratification strategy in acute heart failure: results from the RELAX-AHF trial

Aims We evaluated the added prognostic value of a multi-time point-based multimarker panel of biomarkers in patients with acute heart failure (AHF). Methods and results Seven circulating biomarkers [NT-proBNP, high sensitivity cardiac troponin T (hs-cTnT), soluble ST2 (sST2), growth differentiation factor 15 (GDF-15), cystatin-C, galectin-3, and high sensitivity C-reactive protein (hs-CRP)] were measured at baseline and on days 2, 5, 14, and 60 in 1161 patients enrolled in the RELAX-AHF trial. Patients with BNP >= 350 ng/L or NT-proBNP >= 1400 ng/L, mild to moderate renal impairment, and systolic blood pressure > 125 mmHg were included in the trial. Time-dependent Cox regression analysis was utilized to evaluate the incremental value of serial measurement of biomarkers. Added value of individual biomarkers and their combination, on top of a pre-specified baseline model, was quantified with the gain in the C-index. Serial biomarker evaluation showed incremental predictive value over baseline measurements alone for the prediction of 180-day cardiovascular mortality except for galectin-3. While a repeat measurement as early as day 2 was adequate for NT-proBNP and cystatin-C in terms of maximizing discriminatory accuracy, further measurements on days 14 and 60 provided added value for hs-cTnT, GDF-15, sST2, and hs-CRP. Individual biomarker additions on top of the baseline model showed additional prognostic value. The greatest prognostic gain was, however, attained with the combination of NT-proBNP, hs-cTnT, GDF-15, and sST2, which yielded 0.08 unit absolute increment in the C-index to 0.87 (95% confidence interval 0.83-0.91]. Conclusion In patients with AHF and mild to moderate renal impairment, a multimarker approach based on a panel of serially evaluated biomarkers provides the greatest prognostic improvement unmatched by a single time point-based single marker strategy.